Doors have in the past been used for mounting a variety of exercise devices. Exemplary of such mountings are:
Pollock U.S. Pat. No. 5,254,065 issued Oct. 19, 1993 entitled Flexible Loop Fastening Strap Supportable in Door Structure. In this disclosure, a strap having an enlarged end portion is trapped on one side of the door with a loop depending to the opposite side of the door. The loop acts as the anchored point from which a portion of an exercise device may be attached.
McFall et al. U.S. Pat. No. 5,468,205 issued Nov. 21, 1995 entitled Portable Door Mounted Exercise Apparatus. In this disclosure, two large pulley assemblies are mounted to the top and bottom of a door. The pulley assemblies have elastic members connecting the top pulley assembly to the bottom pulley assembly. The disclosed pulleys have relative large diameters and are canted out of the plane of the door so that they may swivel about an axis tilted toward the person utilizing the exercise device.
Weintraub U.S. Pat. No. 5,601,518 issued Feb. 11, 1997 entitled Portable Exercise Device. In this disclosure, top and bottom U-shaped brackets mount to a door to suspend an otherwise elaborate exercise device. Upper brackets and pulleys together with a lower lever produce a large essentially not portable exercise device.
Mazor U.S. Pat. No. 6,059,698 issued May 9, 2000 entitled Exercise Device for Removable Mounting on a Door. In this disclosure, top and bottom U-shaped brackets form anchor points for exercise devices.
I have discovered that such door-mounted devices suffer from at least two deficiencies. First, most devices mount relatively large mechanical structures to the door in the form of pulleys, levers, top and/or bottom mounted (typically U-shaped) brackets. These large mechanical structures subtract from the exercise device's portability, which is the principle reason for mounting the device to a door in the first place. Secondly, and most importantly, all these devices locally strain the door edges, usually at the top or the bottom of the door. These local strains on the door edges render device mounting damaging to the door and can produce hazardous conditions.
In the following specification, I will refer to the structure of a door. As most are aware, a door closes between two doorjambs with a lintel extending across the door top. Typically, the door is mounted by hinges at one doorjamb and swings to and from positions of engagement of a lock set to the other doorjamb. I describe a door having a closing face and an opening face. The closing face of the door closes into the doorframe consisting of the doorjambs and lintel. The opening face of the door opens out and away from the doorframe. This terminology will be used in the specification and claims that follow.